Vehicular traffic barriers or dividers are in widespread usage. Some of these systems incorporate a plurality of barrier modules disposed end-to-end. Such modules may, for example, be wholly or partially constructed of steel structural elements and/or wholly or partially constructed of concrete. Vehicular traffic barriers or dividers are often employed to separate lanes of traffic or to provide protection for ongoing construction work, and it is known to provide wheels projecting downwardly from the vehicular traffic barriers facilitating repositioning of the barriers.
U.S. Pat. No. 4,666,332, issued May 19, 1987, discloses a traffic barrier carrier or mover enabling connected traffic barrier sections to be repositioned. The carrier includes a supporting frame having two opposite end plates upon which adjacent ends of two generally aligned barrier sections are supported. The frame carriers incorporate a hydraulic cylinder which raises and lowers supporting wheels mounted on an axle under the frame. The wheels are moved between an upper position located above the lower extremities of the supporting frame with the barrier sections being supported on a surface, and a lower position below the lower extremities of the supporting frame with the barrier sections being raised above the surface. In the latter position of the wheels, the barrier sections can be moved from one position to another by a suitable towing vehicle which tows the traffic barrier sections and carriers in a train-like fashion, as needed. This provides an advantage over the commonly employed technique of employing a crane to lift and reposition the barrier sections.
U.S. Pat. No. 5,007,763, issued Apr. 16, 1991, discloses a traffic barrier section with a centrally-located built-in carrier, the carrier including a fluid-operated ram which is connected to an axle carrying wheels below the ram. When the wheels are in a retracted position, the barrier section rests on the ground, and when the wheels are extended the barrier section is fully supported on the wheels. In that latter position, a plurality of barrier sections which are pivotally connected can be moved from one construction site to another as needs change. Each axle and the wheels can be turned to a position other than perpendicular to the longitudinal extent of the barrier section so that some of the barrier sections can be moved transversely to place them in other than a straight line position.
Similar to the system of U.S. Pat. No. 4,666,332, a tow vehicle, such as a tractor, is hooked up to the leading end of the barrier train to pull it to a desired location.
The systems described above have certain deficiencies. When employing a truck, tractor or other tow vehicle the barrier will tend to “wander” due to the pivotal interconnection employed between the modular components or sections. Although it is suggested that steering structure may be associate with the sections, it is still difficult to maintain alignment between the modules and “wandering” of the string of modules while towed.
In addition, the rear ends of the prior art traffic barriers are essentially unprotected during the towing operation. An oncoming vehicle colliding with the exposed rear or tail end of the string can cause not only structural damage but also serious injury to personnel working adjacent to the barrier.
In addition, utilizing the towing approaches, exemplified by the arrangements disclosed in U.S. Pat. Nos. 4,666,332 and 5,007,763 tow vehicles are connected to the front of the string or train of towed modules by connector means centered with respect to the tow vehicle. That is, portions of the tow vehicles project outwardly laterally relative to the barrier. This not only exposes the tow vehicle and its operator to possible impact by passing vehicles, but can interfere with paving or other operations at road construction sites.
U.S. Pat. No. 6,485,224, issued Nov. 26, 2002, discloses a traffic barrier with gate and illustrates use of a pneumatic or hydraulic cylinder arrangement which is employed to move gate support wheels between a retracted position and an extended position wherein rollers engage the roadway or other support surface to facilitate movement of the gate.